This invention relates to a medical appliance, and particularly to an appliance for applying local pressure to a part of the hand for the purpose of stimulating blood circulation through enhanced venous-return flow.
Such medical appliances are known which comprise a double-walled sheath adapted to fit over a limb, for example, an arm or a calf and foot to be treated, and a pump apparatus arranged to inflate and deflate the sheath cyclically, thereby to apply a pumping action to the limb and thus assist venous blood-flow therein.
A particular disadvantage of such known devices is that they cannot be used when the limb to be treated is also to be encased in a plaster cast. Also, they are of inherently large-volume capacity with large area coverage of the involved limb, so that their action is on an entire limb; large-capacity pumping apparatus is required for administration of an inflation/deflation cycle, and more than one pump region may be activated simultaneously, to the detriment of achieving optimum venous-return flow. In particular, these known devices do not permit localized application of pumping pressures.
In our U.S. Pat. No. 4,614,180, we disclose a variety of inflatable devices of relatively low volumetric capacity and specifically adapted to stimulate venous-return flow in a human leg, by localized action beneath the mid-tarsal region of the foot, whereby a major locale of blood accumulation is periodically squeezed, to force or to enhance the force of venous-return flow. The local nature of these inflatable devices enables them to be encased in a cast if necessary, and the toes are always exposed, thus permitting inspection of circulation, swelling, nerve-reaction and other indicia of treatment progress.